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Dangerous Occurrences

If a Dangerous Occurrence occurs in connection with University business it is important that this is reported to the Health and Safety Department immediately for investigation and HSE notification.

Dangerous occurrences apply to all workplaces and include incidents involving, lifting equipment, pressure systems, overhead electric lines, electrical incidents causing explosion or fire, explosions, biological agents, radiation generators and radiography, breathing apparatus, diving operations, collapse of scaffolding, train collisions, wells and pipelines or pipeline works. An outline of the what constitutes a dangerous occurrence in each case is provided below and further information can be found in the additional HSE guidance.

Lifting equipment

The collapse, overturning or failure of any load-bearing part of any lifting equipment, other than an accessory for lifting.

Pressure systems

The failure of any closed vessel, its protective devices or of any associated pipework (other than a pipeline) forming part of a pressure system where that failure could cause the death of any person.

Overhead electric lines

Any plant or equipment unintentionally coming into contact with an uninsulated overhead electric line in which the voltage exceeds 200 volts; or in close proximity with such an electric line, such that it causes an electrical discharge.

Electrical incidents causing explosion or fire

Any explosion or fire caused by an electrical short circuit or overload (including those resulting from accidental damage to the electrical plant) which either results in the stoppage of the plant involved for more than 24 hours; or causes a significant risk of death.


Any unintentional fire, explosion or ignition at a site where the manufacture or storage of explosives requires a licence or registration; or and explosion or ignition of explosives (unless caused by the unintentional discharge of a weapon, where, apart from that unintentional discharge, the weapon and explosives functioned as they were designed to) except where a fail-safe device or safe system of work prevented any person being endangered as a result of the fire, explosion or ignition.

Biological agents

Any accident or incident which results or could have resulted in the release or escape of a biological agent likely to cause severe human infection or illness.

Radiation generators and radiography

The malfunction of a radiation generator or its ancillary equipment used in fixed or mobile industrial radiography, the irradiation of food or the processing of products by irradiation, which causes it to fail to de-energise at the end of the intended exposure period; or equipment used in fixed or mobile industrial radiography or gamma irradiation, which causes a radioactive source to fail to return to its safe position by the normal means at the end of the intended exposure period.

‘Radiation generator’ means any electrical equipment emitting ionising radiation and containing components operating at a potential difference of more than 5 kV.

Breathing apparatus

The malfunction of breathing apparatus where the malfunction causes a significant risk of personal injury to the user; or during testing immediately prior to use, where the malfunction would have caused a significant risk to the health and safety of the user had it occurred during use.

Collapse of scaffolding

The complete or partial collapse (including falling, buckling or overturning) of a substantial part of any scaffold more than 5 metres in height; any supporting part of any slung or suspended scaffold which causes a working platform to fall (whether or not in use); or any part of any scaffold in circumstances such that there would be a significant risk of drowning to a person falling from the scaffold.

Structural collapse

The unintentional collapse or partial collapse of: any structure, which involves a fall of more than 5 tonnes of material; or any floor or wall of any place of work arising from, or in connection with, ongoing construction work (including demolition, refurbishment and maintenance), whether above or below ground.

The unintentional collapse or partial collapse of any falsework.

Explosion or fire

Any unintentional explosion or fire in any plant or premises which results in the stoppage of that plant, or the suspension of normal work in those premises, for more than 24 hours.

Release of flammable liquids and gases

The sudden, unintentional and uncontrolled release: inside a building of 100 kilograms or more of a flammable liquid; of 10 kilograms or more of a flammable liquid at a temperature above its normal boiling point; of 10 kilograms or more of a flammable gas; or in the open air, of 500 kilograms or more of a flammable liquid or gas.

Hazardous escapes of substances

The unintentional release or escape of any substance which could cause personal injury to any person other than through the combustion of flammable liquids or gases.

Additional reporting requirements exist for diving incidents and pipelines. See additional guidance in right hand column for more details.